package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import com.hmdp.service.IVoucherOrderService;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import java.util.Collection;
import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock{

    //用户的名字
    private String name;

    //构造方法注入Redis
    private StringRedisTemplate stringRedisTemplate;

    public SimpleRedisLock(String name, StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }

    //锁的标识
    private static final String KEY_PREFIX="lock";
    private static final String ID_PREFIX= UUID.randomUUID().toString(true)+"-";

    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;

    static {
        UNLOCK_SCRIPT=new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }

    @Override
    public boolean tryLock(long timeoutSec) {

        //获取当前线程的id
        String threadId = ID_PREFIX+Thread.currentThread().getId();
        //获取锁
        Boolean success = stringRedisTemplate.opsForValue().setIfAbsent(KEY_PREFIX + name, threadId, timeoutSec, TimeUnit.SECONDS);

        //success的结果是nil或true
        return Boolean.TRUE.equals(success);
    }

    @Override
    public void unlock() {

        //调用lua脚本
        stringRedisTemplate.execute(UNLOCK_SCRIPT,
                Collections.singletonList(KEY_PREFIX + name),
                ID_PREFIX+Thread.currentThread().getId()
                );


    }
}

//    //获取线程标识
//    String threadId=ID_PREFIX+Thread.currentThread().getId();
//
//    //获取锁中的标示
//    String id=stringRedisTemplate.opsForValue().get(KEY_PREFIX + name);
//
////判断锁标示是否一致
//        if(threadId.equals(id))
//                {
//                //释放锁
//                stringRedisTemplate.delete(KEY_PREFIX + name);
//                }
//









